Fair Value Accounting (Fair Value Inputs, Assets, Quantitative Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring [Member] | Trust Preferred Securities [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit spread embedded in discount rate	4.42%	4.77%
Fair Value, Measurements, Recurring [Member] | Private Equity Investments [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount of lack of liquidity	15.00%	15.00%
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Potential additional payments based on earnings, period	3 years
Fair Value, Measurements, Recurring [Member] | Other Liabilities [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Potential additional payments based on earnings, period	5 years
Fair Value, Measurements, Recurring [Member] | Visa Derivative [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated timing of resolution of covered litigation	1 year
Fair Value, Measurements, Recurring [Member] | Visa Derivative [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated timing of resolution of covered litigation	5 years
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Trust Preferred Securities [Member] | Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, fair value disclosure	$ 1,796	$ 1,745
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Private Equity Investments [Member] | Individual Analysis of Each Investee Company [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, fair value disclosure	25,493	27,148
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Other Liabilities [Member] | Internal Valuation [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, fair value disclosure	14,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Visa Derivative [Member] | Internal Valuation [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, fair value disclosure	$ 5,768	$ 1,415
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Impaired Loans [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Impaired Loans [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	52.00%	80.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring [Member] | Collateral Dependent Impaired Loans [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	25.00%	29.00%
Estimated selling costs	7.00%	7.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Loans Held for Sale [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value		0.00%
Estimated selling costs		0.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Loans Held for Sale [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value		3.00%
Estimated selling costs		10.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Loans Held for Sale [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value		3.00%
Estimated selling costs		7.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	10.00%	20.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Real Estate [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	5.00%	7.00%
Estimated selling costs	7.00%	7.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Assets Held for Sale [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Assets Held for Sale [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	81.00%	35.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring [Member] | Other Assets Held for Sale [Member] | Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	47.00%	31.00%
Estimated selling costs	7.00%	7.00%